Apparatus for sampling workpieces



y 1946- o. E. SCHAUER ET AL 2,400,603

APPARATUS FOR SAMPLING WORKPIECES 'Fild Feb. 6, 1945 2 Sheets-Sheet l INVENTORS I'M 54 BY W 7, m

ATTORNEY y 1946- o. E. SCHAUER ET AL 2,400,603-

APPARATUS FOR SAMPLING WORKPIECES Filed Feb. 6, 1945 2 Sheets-Sheet 2 FIG. 3.

INVENTORS ATTORNEY use.

Patented May 21, 1946 UNITED s'mrss v Parent ounce ABPhRATUS FUR SAMPLING WORKFIECES Ozni-E. Schauer, Cincinnati, and Paul Long,

Middletown, Qhio, assignors to The Cincinnati Eickford Tool Company, Cincinnati, Ohio,

corporation of Ohio Application February 6, 1945, Serial No. 576,480

7 Claims. (Cl. 90-14) This invention has to do with improvements acting means and equipment to enable such specirnensto be taken at the selected zones, of work pieces of non-uniform thickness, which zones may be. spread over a large area of the work, without rendering the piece useless or unserviceable for its intended purpose.

l-leretofore random picked samples of workpieces were drilled with conventional apparatus, and specimens of the work collected and analyzed. The piece so drilled was, however, thereby rendered useless because the extent of tool penetration could not be accurately controlled and sampled pieces were rendered unfit for further With the present invention the extent of tool penetration is positively controlled and it is now possible to take samples of the material from everylworkpiece, without waste, to insure that no piece of low standard is passed.

In the manufacture of propeller blades, for example, the greatest care must be exercised in controlling th composition of the metal and the only way to make certain that a blade composition is up to the required specifications is to sample and analyze the stock in each and at several locations. With the aid of the present invention, each blade may be sampled and analyzed, and if found to be of the required metallurgical composition, passed on for final finishing operations. A main purpose and advantage of the present invention is, that by its aid, the depth of tool penetration is definitely regulated to a distance less than the thickness ordinarily allowed on a work surface for final finishing operations, e. g.,

i d a d e mar s n ident w the sampling operations are removed from the piece during the'subsequent operations thereon.

The ultimate aims of this invention are most satisfactorily attained if each sample taken oompares in volume quite closely with'other samples, which means that the surface of the workpiece from which as many as twenty samples may be taken, must at all locations, lie in a flat plane perpendicular to the sampling tool whereby the latter is caused to penetrate to a given depth uniformly on all sides. In the case of propeller blades which are of non-uniform thickness, one of the sides is selected as the test side and the work holding fixture is so'designed and related to the testing tool and depth controlling mechanism,.that the test side of specimen is clamped in a, fixed plane perpendicular to the axis of the testing tool, irrespective of the irregularities in contour of the opposite side. Toenable such relations to be established and maintained this invention proposes in combination a work holding de-. vice that postitively locates the test side of the specimen with relation to the tool ina manner that automatically equalizes the clamping pressure over that area which pressure is applied from the opposite side, notwithstanding the tapered,

crowned, or otherwise non-uniform contour of that opposite side relative to the test side. By so coordinating and maintaining the test side of the work with the testing tool, workpieces of non-uniform thickness may be sampled, to a specified depth with the assurance that the bottoms of the sampled'zones lie in planes paralleling the original surfaceand that no overcuttin oc curs at one side or the other that islikely to leave sharp corners or other blemishes to give rise to the developments of latent cracks or defects in the finished piece,

Other objects and advantages will be in part indicated in the following description and in part rendered apparent therefrom in connection with which.,

Figure 1 is 'a front View of portions of a drilling machine embodying the invention.

Fig. 2 is a vertical sectional View taken substantially along line 22 of Fig. 1.

Fig. 3 is a plan View of 'a preferred form of positive depth control shim. I

Referring more particularly to Figure 1 of the drawings the invention is illustrated in connection with a machine, commonly referred, to as a radial drill, which comprises a base member 13, an upstanding column (not shown) that supports a radial arm l I, on which is translatably mounted a tool head 12 that rotatably ournals a tool spindle H}. The tool spindle is rotated and translated in a known manner such as more fully disclosed in the patent to Schauer 412,318,336. Hand levers l4 and 15 are each connected to the sleeve 52 as shown more fully in the aforesaid patent,

and are optionally available to translate the spindle upor down, the former affording rapid spindle translation and the latter a relatively slow but more powerful translation.

Within the limits prescribed for the taking of samples without spoiling the work, the conventional depth dial and trip mechanisms of the standard machine are of no use whatsoever, and

means have been devised, herein illustrated asa positive stop mechanism S, carried by the translatable sleeve 52 in which the spindle is journaled,

and cooperating work leveling mechanism .L

mounted on the base l in fixed relation to the spindle l3 and the stop mechanism S related therewith, for obtaining'precision control of tool penetration'to depths of. but a few thousandths, in single or successive steps as may be desired."

The work leveling mechanism L comprises a framing made upvof three main elements, name ly, a base it, an intermediate housing ll,'and.a machined frame-like cover section 18, all bolted or otherwise secured firmlytogether.

The end walls l9 and 29 of the housing section extend somewhat above the tops of the frontand rear walls 2| and 22 forming leg standards for the cover section l8, anda substantial opening;

23 therebeneath. The under surface 24 of the wheel ll.

and shafts 45 and 45 in Fig.2 are turned a slight threaded and receives the threaded portion 39 of a rotatable but non-translatable screw shaft All. 7

distance away from actual position.

With the plane of the test surface of the workpiece definitely leveled and clamped, by the mechanism described, the tool spindle is lowered and the depth of penetration of the tool is positively controlled by the mechanism carried bythe spindle sleeve in cooperation with the leveled 'sur'- face of the clamped workpiece. A preferred form of mechanism for this purpose is illustrated in Figs. 2 and 3 and includes an'externally threaded sleeve 53 that is positively locked by a supplemental rack key 5! to the conventional rack sleeve 52 of the spindle assembly. The lower portions 'of'the'sleeve 5B telescope within a'fiangedexten- I 1 'sion 53 Whose forward end 5 3 extends and is cover section l8 isfinished true 'andits plane ex a tends substantially perpendicular to the axis of the tool spindle l3, and it is against this finished under surface 24 that the workpiece is clamped during the sample taking process.

Withinthe; housing I 1, and resting normally below the openings 23;, and upon upstanding studs 28 is located a self -equalizing work-elevating and work-clamping device. The device herein illus-' trated is composed of two pairs of work-shoes 25 and 26. The pair of shoes 25 are loosely pivoted at-Z'l to the endsof a lever .23, and the latter is pivotally mounted at a midpoint 29 to one end of a transversely extending lever"30.' The other pair of shoes 26 are similarly mounted-upon a lever 3! which is pivotally supported upon the other end 7 of the transverse lever 30. The transverse lever '33 is in turn pivotally mounted, as at 32, between the-endportions of a bifurcated; vertically transj latable, nut element 33, and theH assembly thereby resulting, constitutes a centrally mounted selfequalizing' linkage system that effectively dis tributes a uniform pressure through thefour work shoesas the assembly is elevated off the studs '28 into engagement with the und erside of workpiece Pb. In the instant application of the invention, the workpiece" Pb is apropeller blade having a tapering cross-sectiomand, the selfequalizing action of the work shoes 25, 26 automatically compensates for the variations in thickness, and efiects firm clamping of the upper side of the blade Pb against the fiat under surface 2d of the top section I3 of the unit L. Roller bearadapted to engage the work surface. The exten; sion 53 may move axially of the sleeve til a'limit edfdistanca'the extremes of which is'controlled by a pin 55and slot 56 connection between the members. Provision may be made,-as by one or more extra'tapped holes 57, for changing the range of maximum shift of the extension relative to the sleeve 50. Compensation for the added weight imposed on the spindle sleeve by the stop mechanism S may if desired bev made by adjusting the spindle'counterbalance mechanism ofithe machine or by adding thereto a supplemental" counterbalance mechanism. Patents #1571975, #1,729,583 and #2364318 illustrate devices that may be employed for this purpose.

The threaded upper end of the sleeve iill cara :ries-apair of adjusting nuts 58, between which and the flanged upper end 5% of the extension 53, j

a shim 6!! is inserted. The nuts'EB are: adjusted on the sleeve 50 to a position such that the sum of the thickness of the shim and the length of the extension 53, when the parts are compacted,

, Will cause the. end of the tool T to projectbeyond the work-engaging end 54 of the extension a Pre? cise distance, let us say .905". Accordingly, when I the tool is advanced toward the work, penetration,

thereof into, the work is positively stopped when the extension. 53 has been moved upwardly until its flanged end 59 and shim 6'03 abuts the under surface of the lower of the two nuts 58. By this means tool penetration to an exact depth of .005" is assured. Fig. lillustrates the relation of the parts before the work is engaged, and Fig. 2, fter 7 the work has been engaged and forward tool ing mounted rolls 34 and 35 disposed at the front and rear sides of the openings 23 initially support the propeller blade, and four guide pins 36, placed at'the four corners of the work passage away between the sections' I! and I8, serve properly to guide the blade during: its lateral and vertical movements.

As illustrated more clearly in Fig. 2', the nut element 33 is externally splined to a bushing 31 that is bolted to a reinforced floor 38 within the section 11, and therefore is axially shiftable but nonrotatable. Internally, the splined nut 33 is travel definitely suspended, the latter figure il1ustrating in an exaggerated Way the distance actuallyrtraveled by the tool beyond the end Edof the extension, into the work. 7

On retraction of the tool, the chips resulting from the operation, which have been confined by- V the tubular extension fidarebrushedofi the sur-i face into a removable collecting pan 55 for analysis purposes and appropriately tagged.

If a specimen of the metal composition of th propeller blade is wanted from a'region .005' below the surface, a shim of .005.less in thick:

ness is substituted for the previous shim and the tool spindle again advanced toward the work in the same location. The use of:the .005"1' thinner shim allows the tool to travel .005": fur ther than before, before its advance is positively stopped. A layerof stock .005 thick is thus re moved, and the chips collected in'another pan 66, and appropriately marked.

The herein illustrated form of shim filis'p'referably a composite'of two shima'theone portion 68 thereof being finished to a thickness .005 greater than the other portion 66 with a still further reduced portion 60 intermediate the bearing portions 66 and 60 The shim is formed with an elongated central opening 60 that fits the sleeve 50 and once assembled about the sleeve, cannot fall off. With such a duplex shim on the machine it becomes a simple matter to shift it from one extreme position to the other, between successive feed movements of the tool and thereby repeatedly take samples of two constant and uniform depths from the workpiece. With the instant invention, shims of substantial body and of a wide range of thicknesses may be used.

When a number of samples are to be taken across the workpiece or over a selected area thereof, the workpiece may, of course, be shifted. However, with the invention applied to the radial arm machine herein illustrated, it is more convenient and expeditious to shift the tool head l2 and its spindle stop mechanism S to the various locations. To facilitate such re-locating of the tool, the top section l8 of the leveling unit L is formed with an elongated opening l8 therethrough of such size as will allow substantial tool movement laterally and transversely therein thereby to enable sampling to be quickly effected over large areas of the work with but a single leveling and clamping of the workpiece.

Without further analysis, the foregoing will so fully reveal the gist of this invention that others can, by applying current knowledge, readily adapt it for various utilizations by retaining one or more of the features that, from the standpoint of the prior art, fairly constitute essential characteristics of either the generic or specific aspects of this invention and, therefore, such adaptations should be, and are intended to be, comprehended within the meaning and range of equivalency of the following claims.

Having thus revealed this invention, we claim as new and desire to secure the following combinations and elements, or equivalents thereof, by Letters Patent of the United States:

1. A mechanism for sampling workpieces coinbining, a non-rotatable spindle sleeve adapted to be translated vertically; a tool supporting spindle rotatably journaled in the said sleeve and movable therewith, a non-rotatable intermediate member secured to the exterior of said sleeve and provided with an adjustable abutment, a non-rotatable relatively shiftable member exteriorly mounted upon said intermediate member, said last named, member having an end portion adapted to engage the surface of the work and an opposite end portion cooperatively related to the said abutment carried by said in termediate member; means for maintaining the plane of the surface of the workpiece normal to the axis of said spindle; and a shim interposed between said opposite end portion of the non-rotatable relatively shiftable member and said abutment for limiting the extent of relative movement between said shiftable member and said tool supporting spindle at. a precise point in the downward translation of the tool into-the'-Work. Y s 2;:The combination set. forth in claim .1 in Whichthisaid shim is laterally shiftable and isthickerrat one. end than at the. other. I q

: 34A 1 machine. tool combining .;a,.- rotatable spindle adapted topcarry, a toolya translatable but. non-rotatable sleeve journaling' said spindle; spindle translating means; an abutment member carried by said sleeve, a relatively shiftable member carried by said abutment member having a portion extending, beyondthe spindle end adapted to engage the surface of the work and positively to stop further forward translation of the spindle when the said shiftable member reaches the end of its shift in relation to said abutment member, means for clamping a workpiece with its surface in a plane perpendicular to the line of travel of the tool; and laterally shiftable means carried by said members and interposed between said shiftable member and said abutment member for changing the limit of shift of the shiftable member precise amount correspondingly to advance said spindle rela tive to the work surface a precise amount on a succeeding translation.

4. The combination of claim 3 in which said spindle sleeve is provided with rack teeth and said abutment encircles the spindle sleeve and ber provided with an annular abutment surrounding said sleeve; a secondary sleeve member mounted'on said collar member and movable axially relative to said abutment a limited dis tance, one end of said secondary sleeve being adapted to engage the surface of the workpiece and operative to stop spindle translation after the tool carried by the spindle has penetrated the work a precise distance; means carried by said members and interposable between the opposite end of said secondary sleeve and said annular abutment for changing the limit of shift of said secondary sleeve to effectspindle stopping at a different precise point; and means maintaining the plane of the work surface acted upon by the tool in a fixed relation relative to the axis of the tool spindle.

6. A positive acting depth control for a tool carrying spindle having a translatable but nonrotatable spindle sleeve combining a collared member detachably connected to said non-rotatable sleeve, said collared-member having an annular shoulder, a supplemental sleeve member slidable a limited distance on said member, said sleeve member having a work engaging'forward end portion surrounding the tool and a flanged rear end portion, an elongated slotted spacer member surrounding said collar and disposed between said annular shoulder and the flanged end of said sleeve, said spacer member being laterally shiftable and being of greater thickness at one end than at the other andeffective at one limit of shift to determine the effective length of said supplemental sleeve and at the other limit of its shift to differently determine the effective length of said supplemental latable therewith, an intermediate member secured to said sleeve and provided with an adjustable abutment, a relatively shiftable member mounted upon said intermediate member, said last named member having an end portion adapted to engage the surface of th work and an opposite end portion cooperatively related to the said abutment carried by said intermediate member; and a laterally =shiftable shim-interpos'edbetween said opposite'end portion of. the relatively shiftable member and said abutment 6 for limiting the extentof relative movementbetween said shiftable. memberand said tool-supporting spindle at a precise point in the forward translation of the tool into the work, said shim normally occupying one of'twolefiective'posi tions and; being of greater thickness inoneo said positions; than in the other. V I" I PAUL H. LONG. f 

